1. Field of the Application
The present application relates to the field of turbomachine airfoils for aircraft. More specifically, the present application relates to composite airfoils having a reinforcement structure. The present application also relates to an axial-flow turbomachine having an airfoil according to the present application.
2. Description of Related Art
The compressors and the turbines of an axial-flow turbomachine each comprise a plurality of annular rows of rotor airfoils. The latter make it possible to speed up, slow down, rectify or even deflect an annular flow of air. These actions make it possible to compress the flow, or to recover driving energy from it. The airfoils must be light in weight in order to reduce the mass of the turbomachine, in particular in the aeronautical field. Lightening is also synonymous with reducing the inertia of the rotor.
The optimization of the mass of an airfoil must nevertheless comply with criteria in respect of mechanical strength and thermal resistance. An airfoil must resist vibrations and possibly ingestions into the turbomachine. In addition, the rotor airfoils are confronted with centrifugal forces. In order to produce custom-made airfoils which meet the requirements described above, it is known to design airfoils fitted with reinforcements.
Document EP1450006A1 discloses a compressor airfoil of an aircraft turbofan engine. The airfoil exhibits a body and a reinforcement for its leading edge. The body is made of a composite material charged with fibres, whereas the reinforcement is made of metal. The applied reinforcement is partially anchored in the airfoil, which permits the airfoil to be protected against erosion in the area of its leading edge. Nevertheless, the resistance to impacts and the overall rigidity of such an airfoil remain limited. The presence of skins on the external surfaces makes the airfoil heavier.
Although great strides have been made in the area of composite compressor blades, many shortcomings remain.